(a) Technical Field
The present disclosure is directed to a method of driving a liquid crystal display. More particularly, the present disclosure is directed to a method of driving a liquid crystal display that can dim-drive a light source by selecting a representative luminance value based on the entire luminance distribution of the corresponding image.
(b) Description of the Related Art
Liquid crystal displays are currently among the most widely used flat panel displays, and each includes two display panels on which field generating electrodes such as pixel electrodes and common electrodes are formed, and a liquid crystal layer disposed therebetween. Liquid crystal displays display an image by applying a voltage to a field generating electrode to generate an electric field in the liquid crystal layer, which determines alignment of the liquid crystal molecules of the liquid crystal layer and controls polarization of incident light.
Since a liquid crystal display is not self-emissive, a light source is required. In this case, the light source may be a separately provided artificial light source or a natural light source. Artificial light sources used for liquid crystal displays include light emitting diodes (LED), cold cathode fluorescent lamps (CCFL), and external electrode fluorescents (EEFL).
Recently, a dimming driving method that controls the light intensity of a light source based on the luminance of an entire image have been developed that minimize power consumption and prevent reduction of the image's contrast ratio (CR).
Various methods may be used for selecting a representative luminance value for the corresponding image, but all select a representative value without considering the overall luminance distribution of the corresponding image.
Thus, if a low value is selected as the representative value to reduce power consumption, the luminance of a bright screen may be significantly decreased. On the other hand, if a high value is selected as the representative value to prevent luminance deterioration, light source luminance may be increased even for relatively dim screens, thus contravening the purpose of reducing power consumption.